CHARLESTON, South Carolina (AP) – At South Carolina’s Secession Gala, men in frock coats and militia uniforms and women in hoopskirts will sip mint juleps as a band called Unreconstructed plays “Dixie.”

In Georgia, they will re-enact the state’s 1861 secession convention. And Alabama will hold a mock swearing-in of Confederate President Jefferson Davis.

Across the South, preparations are under way for the 150th anniversary of the Civil War. And while many organizations are working to incorporate both the black and the white experience, there are complaints that some events will glorify the Old South and the Lost Cause while overlooking the fundamental reason for the war: slavery.

“It’s almost like celebrating the Holocaust,” said Benard Simelton, president of the Alabama conference of the National Association for the Advancement of Colored People. “Our rights were taken away and we were treated as less than human beings. To relive that in a celebratory way I don’t think is right.”

Mark Simpson, commander of the South Carolina Division of the Sons of Confederate Veterans, acknowledged that an event such as the Dec. 20 Secession Gala in Charleston is seen by some Americans as politically incorrect. But “to us it’s part of our nature and our culture and our heritage.”

“Slavery was a very big issue. Anyone who denies that has his head in a hole somewhere,” said Simpson, a Spartanburg businessman who counts 32 ancestors who fought for the South. “But slavery was not the single nor primary cause, and that’s where the line gets drawn.”

Simpson said the primary cause was states’ rights — the purported right of states to nullify federal laws and freely leave the Union they voluntarily joined.

Many historians would disagree, and strongly.

“Slavery was the principal cause of the Civil War, period,” said Bob Sutton, chief historian for the National Park Service. “Yes, politics was important. Yes, economics were important. Yes, social issues were important. But when you get to the core of why all these things were important, it was slavery.”

A few weeks before the first shots of the war were fired at Fort Sumter in Charleston Harbor, Confederate Vice President Alexander Stephens called slavery “the immediate cause of the late rupture and present revolution.”

But as the war progressed, the Confederate government shifted its rationale to states’ rights because Davis knew neither England nor other third powers would support the South in a war to preserve slavery, Sutton said.

And after the war, writers and historians who were part of what became known as the Lost Cause movement contended it was fought not over slavery — which they characterized as a benign institution — but over states’ rights.

“The interesting thing about the Civil War, unlike almost any other war, is generally the victor is the one who controls the story,” Sutton said. “The Civil War is different in that the Lost Cause really was the message about the Civil War well into the 20th century.”

That interpretation lingered through the Civil War centennial in the 1960s, during the height of the civil rights movement. The 100th anniversary commemorations tended to focus on the military genius of the South’s generals and the valor of its troops in battle. Slavery was largely ignored.

“The centennial was very popular in the South, in part because Southerners saw that as a real opportunity to dull the civil rights movement,” Sutton said.

For the 150th anniversary, some commemorations are being conducted under state auspices, while others are being privately organized, such as the mock swearing-in in Alabama and the $100-a-head Charleston gala, which will mark the day South Carolina became the first state to secede, Dec. 20, 1860.

The state’s NAACP chapter plans a protest march and vigil outside the city-owned auditorium where the party will be held.

“I don’t care how they try to dress it up — that term ‘putting lipstick on a pig, it’s still a pig’ — they are going to be hard-pressed to find a mixed audience for what they are putting on,” Joe McGill, a black historian from Charleston, said of the Secession Gala.

McGill, who portrays a soldier from the Union’s famed black 54th Massachusetts during re-enactments, sees the 150th anniversary as an opportunity to tell stories that weren’t told 50 years ago, those of blacks and the black units who fought for the Union.

“That is the story we will tell and that is the story African-Americans want to hear,” he said.

During the next four years, there are plans in South Carolina for events that will commemorate the freeing of slaves and the seizure of a Confederate ship by a slave. In Virginia, a conference this fall was called “Race, Slavery and the Civil War: The Tough Stuff of American History.” And last month, black re-enactors from 13 states marched through Harrisburg, Pennsylvania, commemorating a similar parade there at the end of the Civil War.

In the run-up to the secession commemorations, South Carolina’s Ordinance of Secession has been displayed around the state.

David Rutledge, a descendant of David Jamison, who was president of the state’s secession convention, said he nearly cried when he first read it.

“It wasn’t what I expected — a sense of pride — but a sense of sadness because I knew that it came at a very great price and brought on war with all its horrors,” said Rutledge, a lawyer from Greenville whose great-great grandfather was killed in the Battle of the Wilderness.

Rutledge said the war’s entire history should be remembered.

“It is the war of soldiers who fought through it, and they shouldn’t be denigrated because they fought on the wrong side,” he said. “I honor not the Ordinance of Secession itself, but I honor the courage it took to sign it because it came at a terrible price.”

Eric Emerson, director of the South Carolina Department of Archives and History, said he hopes the anniversary events deepen people’s understanding of the war. But he conceded the divide over the war will remain.

“It’s kind of understandable. People want a short answer to everything. That’s why people are hitting each other with these buzzwords: slavery and states’ rights,” he said.